A difficulty with most vehicles, whether of the automotive van type or trailer type is that the interior space is extremely limited. Thus when used as recreational vehicles or campers the accommodations inside the camper must be arranged so that the equipment carried during travel can be compactly stowed to leave room and the kitchen and sleeping accommodations can be used when not on the road. In a van-type camper in particular such storage space is usually inadequate. After a day's travel the driver must transfer his or her equipment in order to free the bunks and the like in the rear for sleeping. Clearly this is a burdensome and time-consuming task, particularly as it must be done at the end of a long day's travel.
An accessory is known for a camper or van which comprises a unit that can sit on top of the vehicle and allow the living space inside it to be increased upwardly. The arrangement comprises in its simplest form an upwardly displaceable roof section normally sitting on top of a relatively large aperture in the vehicle roof. This roof section is carried on articulated arms and is connected at its edges to the edges of the aperture by accordion-type side walls. Thus the roof section can be raised so that it is possible to stand in the vehicle living space, or to use the increased area as a second-floor level.
This last-described arrangement requires extensive alterations to the vehicle on which it is used. Furthermore once installed the arrangement must remain on the vehicle at all times, as the alterations which must be made require permanent mounting of the extension. Furthermore the extension itself is quite expensive and its installation requires expert structural modification of the basic vehicle.